Flow Cytometric Enumeration of Peripheral Blood CD34+ Cells Predicts Bone Marrow Pathology in Patients with Less Than 1% Blasts by Manual Count.

Background and Aims: Significance of absolute number of CD34+ cells in the peripheral blood of patients with less than 1% myeloblasts by manual differential count is unknown and our aim is to study its relevance in clinical practice. Methods: We studied 138 peripheral bloods flow cytometric analyses in patients with less than 1% myeloblasts by manual differential, when CD34+ events were present in the gate that encompassed lymphocytes, monocytes, stem cells, and blasts. Results: The average absolute number of CD34+cells in the peripheral blood was 11 CD34+cells/µL ranging from less than 1 cell/µL to 147 cells/µL. The average absolute number of CD34+ cells in patients with an abnormal expansive process involving bone marrow (metastases, myelodysplasia, granulomas, marrow infections) or if bone marrow biopsy not performed, presumed expansive marrow process was 25 cells/µL, and in patients without an expansive marrow process (or presumed negative) was 4 cells/µL (P<0.00007). Cutoff 12 CD34+ cells/µL had 93% positive predictive value for bone marrow involvement by an expansive process and 78% negative predictive value. Conclusion: Flow cytometric testing of the peripheral blood is extremely sensitive method for enumerating CD34+ cells and can detect fewer than one CD34+ cell/µL. The absolute number of CD34+ cells in the peripheral blood is a useful parameter in determining marrow involvement by an expansive process and may provide guidance with respect to the necessity for bone marrow biopsy.

Three Synchronous Primary Extranodal Mantle Cell Lymphomas Involving Torus Tubarius, Posterior Nasopharynx, and Base of the Tongue 65 Years After Treatment of Chronic Sinusitis with Nasopharyngeal Radium Irradiation.

BACKGROUND Radiation, specifically ionizing radiation, causes broad-spectrum gene damage, including double-strand DNA breaks, single DNA strand breaks, cross links, and individual base lesions, thus causing chromosomal translocations, deletions, point mutations, and, consequently, various types of cancer. Radiation also causes genomic instability in cells, which enhances the rate of mutations in the descendants of the irradiated cell after many generations of normal replications. CASE REPORT We report the first case of mantle cell lymphoma of the torus tubarius, and the first CD10-positive mantle cell lymphoma of the Waldeyer's ring. Mantle cell lymphoma appeared 65 years after treatment of chronic sinusitis with nasopharyngeal radium irradiation. CONCLUSIONS On the basis of the medical literature about atomic bomb survivors, nuclear plant workers, and radiologists exposed to radiation, and our case, we conclude that radiation can, in a very small percentage of exposed individuals, cause non-Hodgkin lymphoma: in 0.24% of atomic bomb survivors and in at least 0.13% of the patients treated with nasopharyngeal radium irradiation. Non-Hodgkin lymphoma can occur many decades after radiation exposure, and individuals treated with nasopharyngeal radium irradiation, usually in their childhood, need continuing follow-up.

Atypical Localization of Malignant Plasma Cells in Non-Viable Cell Area on Flow Cytometry Light-Scatter Dot Plot.

BACKGROUND Multi-parameter (multicolor) flow cytometric study of the bone marrow aspirate is a very useful tool for diagnosis of plasma cell dyscrasia and for evaluation of post-therapy bone marrow for minimal residual disease. CASE REPORT We present a case of a 50-year-old man with multiple myeloma, whose plasma cells on a bone marrow aspirate flow cytometric study showed atypical placement on a light-scatter dot plot, both on forward and side scatter. The bone marrow aspirate sample was 33 hours and 11 minutes old, and the light-scatter dot plot demonstrated that plasma cells, detected by their expression of CD138, CD38, and CD56, occupied an area otherwise characteristic for dead cells and cell detritus. Expressions of CD138 and CD56 were dim (down-regulated). CONCLUSIONS Morphologically atypical plasma cells with irregular nuclear contours/polylobated nuclei from non-fresh samples can present with atypical localization in the area of dead cells. Our study of the multiple myeloma patient with normal localization of plasma cells on a light-scatter dot plot showed a fraction of plasma cells in the dead cell area with dim expression of CD138 and CD56, suggesting that plasma cells may deteriorate (age) rather rapidly, losing surface markers even in less than 24-hour-old specimens. We suggest that the non-viable cell/dead cell area should be checked for expression of CD138 so as not to miss plasma cell dyscrasia, especially if the specimen was run 24 hours after bone marrow sampling.

Coal Mine Dust Desquamative Chronic Interstitial Pneumonia: A Precursor of Dust-Related Diffuse Fibrosis and of Emphysema.

BACKGROUND: Diseases associated with coal mine dust continue to affect coal miners. Elucidation of initial pathological changes as a precursor of coal dust-related diffuse fibrosis and emphysema, may have a role in treatment and prevention. OBJECTIVE: To identify the precursor of dust-related diffuse fibrosis and emphysema. METHODS: Birefringent silica/silicate particles were counted by standard microscope under polarized light in the alveolar macrophages and fibrous tissue in 25 consecutive autopsy cases of complicated coal worker's pneumoconiosis and in 21 patients with tobacco-related respiratory bronchiolitis. RESULTS: Coal miners had 331 birefringent particles/high power field while smokers had 4 (p<0.001). Every coal miner had intra-alveolar macrophages with silica/silicate particles and interstitial fibrosis ranging from minimal to extreme. All coal miners, including those who never smoked, had emphysema. Fibrotic septa of centrilobular emphysema contained numerous silica/silicate particles while only a few were present in adjacent normal lung tissue. In coal miners who smoked, tobacco-associated interstitial fibrosis was replaced by fibrosis caused by silica/silicate particles. CONCLUSION: The presence of silica/silicate particles and anthracotic pigment-laden macrophages inside the alveoli with various degrees of interstitial fibrosis indicated a new disease: coal mine dust desquamative chronic interstitial pneumonia, a precursor of both dust-related diffuse fibrosis and emphysema. In studied coal miners, fibrosis caused by smoking is insignificant in comparison with fibrosis caused by silica/silicate particles. Counting birefringent particles in the macrophages from bronchioalveolar lavage may help detect coal mine dust desquamative chronic interstitial pneumonia, and may initiate early therapy and preventive measures.

Primary Urinary Bladder Angiosarcoma with Osteoclast-Like Multinucleated Giant Cells: A Case Report and Literature Review.

BACKGROUND: Angiosarcoma is a fatal and aggressive mesenchymal tumor. It occurs in skin, breast, and parenchymal organs. It rarely arises primarily in the urinary bladder. Only 13 cases of primary urinary bladder angiosarcoma have been reported in the English literature. CASE REPORT: The patient was a 68-year-old man who presented to the Emergency Department with inability to void. Computed tomography of the abdomen and pelvis showed a urinary bladder mass. Surgical excision of the mass was performed. Pathological examination results were consistent with angiosarcoma. In addition to the unusual location of this tumor, the pathology was different from the previously reported cases in that this case was rich with osteoclast-like multinucleated giant cells. CONCLUSIONS: The pathological diagnosis of primary urinary bladder angiosarcoma is challenging. Histological patterns and immunophenotypes are variable. Here, we review all reported cases of primary urinary bladder angiosarcoma, highlight the clinical and morphological features of this malignant neoplasm, and report a unique case of primary urinary bladder angiosarcoma with osteoclast-like multinucleated giant cells.

Nodal Marginal Zone Large B-Cell Lymphoma with Burkitt Translocation and Complex Chromosomal Changes Associated with Overexpression of BCL2, MYC, and BCL6.

We report the first case of a nodal marginal zone large B-cell lymphoma and the first with MYC rearrangement. This high proliferation rate lymphoma (40% of cells) occurred in the bilateral cervical, axillary, and para-aortic lymph nodes of an 82 year old woman. It involved extensively her bone marrow, and was lethal. Malignant B-cells were CD10 negative, harbored Burkitt translocation, and multiple chromosomal changes including trisomies of chromosomes 3 and 18, and three copies of 8q with an intact q24 cytoband (in addition to MYC rearrangement), associated with overexpression of BCL6, BCL2, and MYC respectively. We suggest that in aggressive nodular marginal zone lymphomas (clinical picture or high proliferation rate of lymphoma cells), fluorescence in situ hybridization analysis for MYC rearrangement, with break-apart probe, and for MYC/IGH translocation, in addition to chromosome analysis, should be performed. MYC rearrangement associated with a more rapid progression of the neoplasia, might warrant a more aggressive treatment.

Hematogones in the peripheral blood of a 5½-month-old boy with cyclic neutropenia due to heterozygous, novel ELANE gene mutation p.Q97P, c.290 A>C.

We have identified a novel point mutation in the ELANE gene of a 5.5-month-old boy with severe cyclic neutropenia, and we are reporting for the first time, to our knowledge, the presence of hematogones in the peripheral blood of an infant. The novel point mutation occurred at base number 290 in codon 97, where adenine was replaced with cytosine. The mutation caused the replacement of amino acid glutamine with amino acid proline in the activation domain of the elastase 2 enzyme. The heterozygous mutation generated severe cyclic neutropenia, granulocytic maturation arrest, an increased number of hematogones (26% of marrow cells) in the bone marrow, an absence of neutrophils, and the presence of stage 3 (mature) hematogones in the peripheral blood. The percentage of hematogones in the peripheral blood was inversely proportional to the absolute number of neutrophils. Leukemic number of blast-like cells (hematogones) in the bone marrow, blast-like cells in the peripheral blood, marked neutropenia, and the arrest of granulopoiesis might suggest an acute leukemia. However, the finding of characteristic flow cytometric features of hematogones should help to avoid a wrong diagnosis.

Biological contamination of insulin pens in a hospital setting.

PURPOSE: Biological contamination of insulin pens in a hospital setting was studied. METHODS: This prospective study, conducted at two hospitals within a multihospital system, examined 125 insulin pens that had been returned to the inpatient pharmacies after patient discharge and were refrigerated for up to 48 hours before laboratory testing. Insulin was removed from the 125 pens and examined microscopically for the presence of nucleated cells and red blood cells (RBCs). Positive samples were examined by a pathologist to determine the cell types present. An immunochromatographic assay was used to determine the presence of free hemoglobin in the insulin. The 10 control samples were negative on microscopic examination. RESULTS: Out of 125 insulin pens, 7 (5.6%) tested positive for cells or hemoglobin. Microscopic examination revealed six positive samples containing a total of nine cells, including macrophages, squamous cells, and an RBC. The sample containing the RBC was not the same sample that tested positive for hemoglobin. Based on findings of intact cells and hemoglobin in insulin pens after administration, the potential exists for transmission of infectious agents from patient to patient if a single pen cartridge is used to administer insulin to multiple patients, even if a new needle is used for each individual. CONCLUSION: Examination of 125 insulin pens used in hospitals revealed hemoglobin in 1 pen and at least one cell in another 6 pens. The nine detected cells consisted of four squamous epithelial cells, four macrophages, and one RBC.

Calcifying nanoparticles associated encrusted urinary bladder cystitis.

Encrusted cystitis is a subtype of chronic cystitis characterized by multiple calcifications in the form of plaques located in the interstitium of the urinary bladder mucosa and frequently associated with mucosal ulcers. It is a very rare disease of controversial etiology. Our transmission electron microscopy of the calcified plaques of encrusted cystitis has revealed that the smallest formed particles (elementary units) of these calcifications are electron-dense shells surrounding an electron lucent core, diagnostic of calcifying nanoparticles (previously called nanobacteria). We pioneer the notion that calcifying nanoparticles are the causative agents of encrusted urinary bladder cystitis.

Nanobacteria-associated calcific aortic valve stenosis.

Calcific aortic valve stenosis is the most common valvular disease in developed countries, and the major reason for operative valve replacement. In the US, the current annual cost of this surgery is approximately 1 billion dollars. Despite increasing morbidity and mortality, little is known of the cellular basis of the calcifications, which occur in high-perfusion zones of the heart. The case is presented of a patient with calcific aortic valve stenosis and colonies of progressively mineralized nanobacteria in the fibrocalcific nodules of the aortic cusps, as revealed by transmission electron microscopy. Consistent with their outstanding bioadhesivity, nanobacteria might serve as causative agents in the development of calcific aortic valve stenosis.

Primary cutaneous follicle center lymphoma of the arm with a novel chromosomal translocation t(12;21)(q13;q22): a case report.

We report a reciprocal translocation between the long arms of chromosomes 12 and 21, t(12;21)(q13;q22), in a patient with primary cutaneous follicle center lymphoma. Follicle center lymphoma of the skin and follicle center cell lymphoma of the lymph node are morphologically and immunophenotypically very similar. However, the clinical behavior and prognosis of these tumors are different due to the molecular basis of these malignancies. Follicle center cell lymphoma of the lymph node is determined by the presence of a unique translocation between chromosomes 14 and 18, t(14;18)(q32;q21), BCL-2-JH gene rearrangement, that is not present in primary cutaneous follicle center lymphomas. Chromosomal translocations in the primary skin lymphomas have not been previously reported. We hope that our discovery of a new translocation t(12:21)(q13q22) will encourage further investigation into the molecular basis of this translocation and other cytogenetic abnormalities in primary cutaneous B-cell lymphomas.

Primary, extranodal, follicular non-Hodgkin lymphoma of the gallbladder: case report and a review of the literature.

We report the first case of isolated primary extranodal non-Hodgkin lymphoma follicular grade 2 limited to the gallbladder, found in the laparoscopic cholecystectomy specimen from a 70 year old woman with symptomatic cholelithiasis. The pericystic duct lymph node, surgical margins, and other lymph nodes, were not involved with lymphoma. According to the medical literature in English language, mucosa associated lymphoid tissue lymphoma (6 cases) is the most frequent type (38%) of primary gallbladder lymphomas (15 reported cases plus our case). Our case demonstrates that follicular lymphoma can be limited to the gallbladder, and confirm that it can occur in an organ normally devoid of lymphoid tissue.

Nanobacteria-caused mitral valve calciphylaxis in a man with diabetic renal failure.

We have found that nanobacteria, recently discovered Gram-negative atypical bacteria, can cause local calciphylaxis on the mitral valve in a setting of high-calcium X phosphorous product in the blood. We present the case of a 33-year-old man with diabetic renal failure on continuous ambulatory peritoneal dialysis who died as a result of multiple brain infarcts due to embolizations from mitral valve vegetations. Systemic calciphylaxis was not present. Spectrometric analysis of the mitral valve vegetations showed that they were composed of calcium phosphate, carbonate apatite form, and fibrin. The electron microscopy of the thrombotic vegetation demonstrated nanobacterium as a nidus for carbonate apatite formation. Investigation for the presence of nanobacteria in the multiple organs involved in systemic calciphylaxis may be of help in elucidating the pathogenesis of this frequently fatal disorder.

Correlation between the percentages of myeloblasts in bone marrow obtained by flow cytometry and manual counting on glass slide smears in 74 hematologic patients.

To investigate reliability of calculating percentage of myeloblasts by flow cytometric method, data were obtained from 74 hematologic patients (76 paired data). Myeloblast counts obtained by manual count versus flow cytometry were compared. Our data show that the percentage of myeloblasts in the bone marrow obtained with flow cytometric method correlates well with manual count (correlation coefficient is 0.9912). A very high correlation coefficient means that reliable percentage of myeloblasts in the bone marrow can be obtained by either method alone. Flow cytometry is a useful adjunct (or quality control) to validate manual myeloblast count and vice versa.